PIONEERING research into DNA to turn one species into another by Manchester scientists could have major consequences for the production of genetically modified crops.

For the first time, a team at Manchester University has found a way of making two forms of yeast so similar that they can breed successfully to create fertile offspring.

Normally, closely related species produce healthy, but infertile offspring. For instance, when horses and donkeys breed they produce mules which are sterile.

But by tinkering with two similar, but different forms of humble yeast, the biological scientists have managed to change them enough to create fertile offspring.

And the breakthrough could mean that GM crops could be engineered so that cross-breeding with wild crops could be eradicated.

Much opposition to the GM movement stems from fears that engineered produce could cross-pollinate with naturally occurring crops and either spread out of control or produce an uncontrolled mutant offspring.

Enhance

Professor Stephen Oliver explained that what they have achieved could stop this.

"By making these changes we could enhance a GM species with a barrier to prevent them cross-breeding," he said.

"This would keep them locked into the particular crop species and prevent spreading them to any wild species nearby."

The scientists engineered the chromosomes of brewer's yeast, Saccharomyces cerevisiae, to make it indistinguishable from a related species.

The Manchester team rearranged the brewer's yeast chromosomes so they were sufficiently similar that the two could interbreed.

Prof Oliver said what they had learned from the engineering could also have implications for commercial breweries.

"We can quickly tell if something is seriously wrong and if the brewery needs to change its yeast."